In normal healthy adults, supplementation with nutraceuticals is not required. Supplements should only be consumed under medical supervision. The vegetarian diet consumed in South Asia often is rich in oil and dairy products. This is not good for health. To make this diet nutritious, oil and dairy products need to be reduced to the minimum.
A plant-based diet, though, is good for health. Multiple studies have shown that this diet is excellent in preventing cardiovascular diseases, cancer, and diabetes. Plants are rich in fiber, antioxidants, and essential minerals. People who are exclusively consumers of a plant-based diet show deficiencies of iron, Omega 3 fatty acids, and vitamin B12.
Iron obtained from plants is of poorer nutritional quality than heme iron that is obtained from red meat. Non-heme iron is provided mainly by plant-based foods like whole grains, legumes, lentils and nuts, dairy products, and iron-fortified foods. The usefulness of supplementation and its relationship to health, though, is not yet fully established.
Vitamin B12 is obtained from dairy products, and the best sources of Omega3 fatty acid are available from fatty fish. Plant-based sources of Omega3 are flaxseed, chia seeds, canola, walnut and soybean oils, leafy and green vegetables. These are short-chain omega 3 molecules that need to be converted in the body into long-chained fatty acids. Converting plant-based omega3 foods into nutritionally useful forms is an inefficient metabolic process. The absorption levels of this type of fatty acid are quite low.